Breathing Rate Estimation from Head-Worn Photoplethysmography Sensor Data Using Machine Learning Sensors 2022, 22, 2079 https://doi.org/10.3390/s22062079 https://mdpi-res.com/d_attachment/sensors/sensors-22-02079/article_deploy/sensors-22-02079-v2.pdf?version=1646789843 Important paper the Dalai Lama should read.
